WO2017137184A1

WO2017137184A1 - Bearing device for a leaf spring assembly of a wheel suspension

Info

Publication number: WO2017137184A1
Application number: PCT/EP2017/050294
Authority: WO
Inventors: Thomas RUPFLIN; Peter Hofmann
Original assignee: Zf Friedrichshafen Ag
Priority date: 2016-02-10
Filing date: 2017-01-09
Publication date: 2017-08-17
Also published as: KR20180110056A; DE102016201965A1; CN108602408A; US20190329619A1; EP3414116A1; JP2019511409A

Abstract

The invention relates to a bearing device (7) for a leaf spring assembly (1) of a wheel suspension, comprising a leaf spring (2) and a connection mechanism which is used for connecting the leaf spring (2) to a vehicle body and which includes a bolt (10). In order to create a bearing device (7) that is characterized by a compact design and low production costs, the leaf spring (2) is made of a fiber composite material and is transversely penetrated by a through-hole (11) through which the bolt (10) passes.

Description

Bearing device for a leaf spring assembly of a suspension

The invention relates to a bearing device for a leaf spring arrangement of a wheel suspension, comprising a leaf spring and a connecting device which serves to connect the leaf spring to a vehicle body, wherein the connecting device has a bolt. Furthermore, the invention relates to a leaf spring arrangement comprising an aforementioned bearing device.

In chassis of vehicles, at least one extending in the vehicle transverse direction leaf spring may be provided as a suspension spring, which supports the structure of the vehicle resiliently with respect to the wheels provided on the wheels. Corresponding transverse leaf springs can be used in wheel guide units, which are designed as independent wheel suspensions, as rigid axles or a special form of rigid axle forming composite link axles. Twist beam axles are used predominantly as a rear axle on small and mid-size vehicles with front-wheel drive and are a cost-effective and space-saving design that is easy to mount on the vehicle.

Transverse leaf springs can also be provided in principle for suspensions with independent suspension, in which case the respective wheel is articulated, for example via a Mehrfachanlenkung and optionally via an auxiliary frame on the vehicle body and supported on the transverse leaf spring on this.

Transverse leaf springs, which are used as suspension springs in suspension, can be formed by a single leaf-shaped spring element or by a plurality of arranged in a spring assembly leaf-shaped spring elements. The advantages of using a transverse leaf spring over the use of coil springs consist in lower costs, a smaller space requirement, a self-damping behavior of the leaf spring and possibly a stabilizer effect of the transverse leaf spring. At its two ends, the transverse leaf spring is either provided with recordings, via which it is guided on the wheel carriers, or the leaf spring ends are based on recordings which are provided directly on the wheel carriers. In addition, the transverse leaf spring is usually connected to the structure in a region between the two ends, which is respectively spaced therefrom, directly or via an auxiliary frame on bearing devices.

From DE 10 2013 218 055 A1 discloses a bearing device for a leaf spring arrangement, in which a leaf spring is connected via a connecting device to a vehicle body. The leaf spring is arranged in the region of a vehicle axle as a transverse leaf spring and is connected via a bolt of the connecting device to the vehicle body, wherein the bolt is passed through to a holding device.

Based on the above-described prior art, it is an object of the present invention to provide a bearing device, which is characterized by a compact design and low production costs.

This object is achieved on the basis of the preamble of claim 1 in conjunction with its characterizing features. The following dependent claims give each advantageous embodiments of the invention. A leaf spring assembly with a bearing device is further subject matter of claim 10.

According to the invention, a bearing device comprises a leaf spring and a connecting device which serves to connect the leaf spring to a vehicle body. In this case, the connecting device has a bolt, via which the connection to the vehicle body is made. According to the invention, the leaf spring can be formed by a single leaf-shaped spring element or by a plurality of spring elements, which are then combined to form a spring assembly.

The bearing device is then preferably part of a leaf spring arrangement for a wheel suspension of a motor vehicle, wherein the leaf spring is provided in particular as a transverse leaf spring, ie it is installed in the transverse direction of the motor vehicle. Here, the leaf spring takes Radführungsaufgaben, in addition, a stabilizer effect and depending on the structure of the leaf spring also an internal damping behavior can be caused. On the body side, the leaf spring is then connected via at least one, but preferably two bearing devices, via which the forces introduced into the leaf spring are supported on the vehicle body.

The invention now includes the technical teaching that the leaf spring is made of a fiber composite material and traversed transversely with a recess through which the bolt is passed. In other words, the leaf spring thus consists of a fiber composite material and has a recess which extends transversely through the leaf spring, i. penetrates the leaf spring in a transverse direction. Through this recess, the bolt of the connecting device is passed.

Such an embodiment of a bearing device for a leaf spring arrangement has the advantage that the bearing device can be realized due to the passage of the bolt through the leaf spring with a low number of components. Accordingly, the bearing device is characterized by a low manufacturing cost and also a compact design, as well as a low weight. At the same time, lateral and vertical forces can be reliably absorbed. Finally, a large number of identical parts can be used.

In contrast, the bolt of the bearing device of DE 10 2013 218 055 A1 is performed by a holding device which is placed on the leaf spring. This increases the space and also the production costs accordingly. Furthermore, this is accompanied by an increase in weight.

According to the invention, the recess of the leaf spring extends in a transverse direction of the leaf spring, which means, in the case of a transverse leaf spring in the installed position, an orientation of the recess in the vehicle longitudinal direction. Transverse direction thus means an orientation in the direction of a transverse axis orthogonal to a longitudinal axis and a vertical axis of the leaf spring. The recess may be subsequently introduced into the leaf spring, ie, with appropriate removal of material, or the recess is already defined in the course of production of the leaf spring. In particular, the recess has a circular cross-section, but it could also be deviating designs. Furthermore, the recess preferably extends through the neutral fiber of the leaf spring.

The fiber composite material of the leaf spring is preferably GFRP (glass-fiber reinforced plastic), since this makes it possible to realize a suitable characteristic of the leaf spring with at the same time low weight. Alternatively, it may also be a different fiber-plastic composite or other fiber composite material.

According to one embodiment of the invention, the bolt takes on both sides of the leaf spring lying clamping devices, which are biased towards each other on the bolt and thus against the intermediate leaf spring. In this way, a reliable mounting of the leaf spring can be realized, since the clamping devices clamp the leaf spring and thus prevent unwanted relative movements here.

In a further development of the aforementioned embodiment, the clamping devices each comprise a clamping sleeve, wherein the clamping sleeves are further preferably each provided on the side of the leaf spring, each with a conical and / or cylindrical magnification, with which the respective clamping sleeve is biased against the leaf spring. Thus, a clamping of the intermediate leaf spring can be realized in an advantageous manner. Due to the conical and / or cylindrical enlargements, the contact surface can be increased, so that a sufficient support of forces takes place.

According to a further embodiment possibility of the aforementioned embodiment, a respective contact element is provided between the leaf spring and the respective clamping sleeve of the respective clamping device, which is stretched over the respective clamping sleeve against the leaf spring. In further education shows the respective Investment element clamp-like approaches, with which it surrounds the leaf spring from the side of the respective clamping device. By gripping the leaf spring by the biased against the leaf spring contact elements, the fixation of the leaf spring in this area is further improved, since unwanted relative movements of the leaf spring are positively locked to the connecting device.

A fixation could in the sense of the invention, but also purely non-positively via the sleeves, which are then provided with sufficient force support either with a correspondingly large diameter or the conical and / or cylindrical enlargements. Furthermore, contact surfaces of the connection means with the leaf spring may generally be provided with surfaces of higher roughness, such as knurls.

It is a further embodiment of the invention that the connecting device comprises rubber bearings over which the connection to the vehicle body is made. In development of this embodiment, the rubber bearings are placed in each case on the respective clamping sleeve. Advantageously, this dampens the transmission of sound and vibrations to the vehicle body.

According to a possible embodiment of the invention, the bias of the clamping devices is realized via a screw. As a result, the bias of the clamping devices can be realized in a simple manner. Preferably, the bolt is provided for this purpose at least one end with a thread. Specifically, the bolt can be designed as a screw, wherein a nut is placed on the end-side thread, wherein a screw head and the nut bias the intermediate components of the clamping devices against each other. The bolt could also be designed as a threaded bolt, which is equipped at both ends with threads and here receives associated nuts, which in turn bias the jigs against each other.

The invention is not limited to the specified combination of the features of the main claim or the claims dependent thereon. There are also possibilities, individual features, even as far as they are from the claims, the following description of preferred embodiments of the invention o- emerge directly from the drawings to combine with each other. The reference of the claims to the drawings by use of reference numerals is not intended to limit the scope of the claims.

Advantageous embodiments of the invention, which are explained below, are shown in the drawings. It shows:

Fig. 1 is a schematic representation of a leaf spring assembly;

Fig. 2 is a perspective view of a bearing device of the leaf spring assembly of Fig. 1, according to a first embodiment of the invention;

Fig. 3 is a sectional view of the bearing device of Fig. 2;

4 shows a perspective view of a bearing device of the leaf spring arrangement from FIG. 1, according to a second embodiment of the invention;

Fig. 5 is a sectional view of the bearing device of Fig. 4; and

Fig. 6 is a sectional view of a bearing device of the leaf spring assembly of Fig. 1, according to a third embodiment of the invention.

FIG. 1 shows a schematic view of a leaf spring arrangement 1, which is used in a wheel suspension of a motor vehicle. The leaf spring assembly 1 comprises a leaf spring 2 made of a fiber composite material, which is preferably GFRP (glass fiber reinforced plastic). In this case, the leaf spring 2 may be single-layered or composed of several individual layers, which are combined to form a package.

The leaf spring 2 is in the installed state of the leaf spring assembly 1 at their ends 3 and 4 via receptacles 5 and 6 with wheel carriers of the respective vehicle axle. prevented. In this respect, the leaf spring 2 is then installed as a transverse leaf spring, which is transverse to the direction of travel of the motor vehicle. Between the two ends 5 and 6, the leaf spring 2 is also connected in the installed state of the leaf spring assembly 1 to storage facilities 7 and 8 with a vehicle body.

FIGS. 2 and 3 show a first embodiment according to the invention of the bearing devices 7 and 8 using the example of the bearing device 7, wherein the bearing device 8 corresponds to the embodiment described. As can be seen, the bearing device 7 comprises a connecting device 9 with a bolt 10, which is guided through a recess 11 of the leaf spring 2, which can be seen in FIG. 3. The recess 11 passes through the leaf spring 2 transversely in the region of an indicated in Fig. 2 thickening 12 and in the region of a neutral fiber of the leaf spring second

The bolt 10 is in the present case designed as a screw and carries on both sides of the leaf spring 2 lying clamping devices 13 and 14, which are each composed of a clamping sleeve 15 and 16 and a contact element 17 and 18 respectively. The clamping devices 13 and 14 are connected via a screw head 19 of the

Screw executed bolt 10 and guided on an end-side thread of the bolt 10 nut 20 toward each other and thus biased against the intermediate leaf spring 2.

As can be seen in Fig. 3, the contact elements 17 and 18 each have a respective bracket-like projection 21 and 22, with which the respective contact element 17 and 18, the leaf spring 2 engages around from the respective side. The lugs 21 and 22 each have bevels 23 and 24, which claw in the course of biasing the jigs 13 and 14 against the leaf spring 2 in the material derselbigen. Contact surfaces of the projections 21 and 22 with the leaf spring 2 can also be designed with a higher surface roughness, for example, by a corresponding knurling of the surfaces. On the clamping sleeves 15 and 16 are also - not shown in the present case - placed rubber bearing over which in the installed state of the leaf spring assembly 1 of FIG. 1, the connection to the vehicle body is made.

4 and 5 show an alternative embodiment of the storage facilities 7 and 8 according to a second embodiment of the invention. Again, this embodiment possibility is described with reference to the bearing device 7, wherein the bearing device 8 is constructed analogously thereto.

The embodiment according to FIGS. 4 and 5 essentially corresponds to the variant according to FIGS. 2 and 3, in contrast to which tensioning devices 25 and 26 have no contact elements, but instead bias clamping sleeves 27 and 28 directly against the intermediate leaf spring 2. In this case, the clamping sleeve 27 and 28 on the side of the leaf spring 2 each have a conical and / or cylindrical magnification 29 and 30, with which they are biased against the leaf spring 2. Alternatively, a special contour can be used to minimize the surface pressure on the spring, for example according to the train-triangle method. Otherwise, the possibility of embodiment according to FIGS. 4 and 5 corresponds to the variant according to FIGS. 2 and 3, so that reference is made to the description described here.

Finally, FIG. 6 shows a further alternative embodiment of the bearing devices 7 and 8 according to a third variant of the invention, which is described by way of example with reference to the bearing device 7. The storage device 8 is constructed analogously thereto.

Deviating are clamping sleeves, of which in the present case only the clamping sleeve 31 can be seen in the contact area with the leaf spring 2 executed enlarged. In the case of the variant according to FIG. 6, the rubber bearing 32 placed on the clamping sleeve 31 can also be seen. Incidentally, the embodiment possibility according to FIG. 6 corresponds to the variant according to FIGS. 4 and 5, so that reference is made to the description described here. By means of the embodiments according to the invention, in each case a bearing device can be provided, which is characterized by a compact construction and a low production outlay.

Reference symbol leaf spring arrangement

leaf spring

The End

admission

Storage facility

connecting device

bolt

recess

thickening

jig

clamping sleeve

contact element

screw head

mother

approach

bevel

jig

clamping sleeve

Conical enlargement

clamping sleeve Rubber bearing

Claims

claims

A bearing device (7; 8) for a leaf spring arrangement (1) of a wheel suspension, comprising a leaf spring (2) and a connecting device (9), which serves to connect the leaf spring (2) to a vehicle body, wherein the connecting device (9 ) has a bolt (10), characterized in that the leaf spring (2) made of a fiber composite material and having a recess

(11) is transversely penetrated, through which the bolt (10) is passed.

Second bearing device (7; 8) according to claim 1, characterized in that the bolt (10) on both sides of the leaf spring (2) lying clamping devices (13, 14, 25, 26) receives, which on the bolt (10) towards each other and thus biased against the intermediate leaf spring (2).

3. bearing device (7; 8) according to claim 2, characterized in that the clamping devices (13, 14; 25, 26) each comprise a clamping sleeve (15, 16; 27, 28, 31).

4. bearing device (7; 8) according to claim 3, characterized in that the clamping sleeves (27, 28) respectively on the side of the leaf spring (2) each with a conical and / or cylindrical enlargement (29, 30) are equipped, with which the respective clamping sleeve (27, 28) is biased against the leaf spring (2).

5. bearing device (7; 8) according to claim 3, characterized in that between the leaf spring (2) and the respective clamping sleeve (15, 16) of the respective clamping device (13, 14) each a contact element (17, 18) is provided, which is stretched over the respective clamping sleeve (15, 16) against the leaf spring (2).

6. bearing device (7; 8) according to claim 5, characterized in that the abutment element (17, 18) has clamp-like projections (21, 22), with which it the leaf spring (2) from the side of the respective clamping device (13, 14) embraces.

7. bearing device (7; 8) according to claim 1, characterized in that the connecting device (9) rubber bearing (32), via which the connection to the vehicle body is made.

8. bearing device (7; 8) according to claim 3 and 7, characterized in that the rubber bearings (32) are each placed on the respective clamping sleeves (31).

9. bearing device (7; 8) according to claim 2, characterized in that the bias of the clamping devices (13, 14; 25, 26) is realized via a screw.

10. leaf spring assembly (1) for a suspension of a vehicle, comprising a leaf spring (2) which is connected by a vehicle body via at least one bearing device (7, 8) according to one or more of claims 1 to 9.